Baffle type muffler with retroverted flow



P. J. MAY

BAFFLE TYPE MUFFLER WITH RETROVERTED FLOW Oct. 11, 1949.

2 Sheets-Sheet 1 Filed Dec. 8, 1945 Ezra-.1

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P. J. MAY

BAFFLE TYPE MUFFLER WITH RETROVERTED FLOW Oct. 11, 1949.

w 1 M v I J w 2 I w a w m PM .2 1d I M m lmrlm m w wwwww 0 DO 0 O O OHHM Jm M mm m m ww \N m M o WWW w Patented Oct. 11, 1949 STATES PATENTOFFIE BAFFLE TYPE MUFFLER WITH RETROVERTED-1FLOW Patrick J. May, SanFrancisco, Calif. Application December 8, 1945, Serial No. 633,760

(CL ISL-53) 3 Claims.

-My invention relates to improvements in internal combustion enginemufflers, and more particularly to a two-piece muflier housingcomprising upper and lower sections in which are positioned a series ofperforated baffle plates and deflector plates, together with a pair ofbaffles at-the'rear end of the muffler which traps any exhaust noisesand simultaneously directs the exhaust gasses towards the: front of themuffler and finally-over a rearwardly extending solid baffle to theexhaust end of the muffler.

'An" object of my invention is to provide an improved form of mufflerwhich will be substantially rectangular in cross section and which willcomprise a plurality of perforated baffles and a baffle trap, wherebythe exhaust noises incident toan internal combustion engine will be.silenced, and at the same time the construction of the muffler willprevent any trapping or pockets of the exhaust gasses in the muflier,thereby enhancing the eflicient operation of the internal combustionengine to" which it is attached.

A further object of my invention is to provide a highly efficient formof muffler for an internal combustionengine which will reduce backpressure and pocketing of the exhaust gasses to a minimum, whilemuffiing and silencing the exhaust noises from the internalcombustion-engine to which the muffler is attached.

Other objects will appear as proceeds.

In the accompanying part of my application,

Figure I is a top plan view of my improved muffler;

Figure, mufller;

Figure 3 is an end view of my muffler;

"Figure 4' is a longitudinal sectional view through the muffier;

Figure 5 is a transverse sectional view taken on the line 5-5' of Figure4;

Figure 6' is a transverse sectional view taken on the line 6-6 of Figure4;

Figure. '7 is a partial sectional view taken on the line 1-4 of. Figure4 and Figure :8 is a sectional view taken on the line 8---,8 of- Figure4.

Like characters of reference are used throughout; the. followingspecification: and the accom-e drawings to designate correspondingmintsm carrying out my inventionl provide a muffler heusing'havinganupper section i and alower drawings which form. a

2' is a side elevation of my improved the description section 2substantially rectangular in shape and held together by means of thebeads 3 on the opposite sides of the upper section and the flanges 4 onthe opposite sides of the lower section, which are crimped together toform a substantially rigid muffler housing. Theopposite ends of themuffler housing are tapered as at 5 and 6 and terminate in thecylindrical ends I and 8, which will be connected respectively to theexhaust manifold of an internal combustion engine (not shown), and tothe exhaust tail pipe (also not shown).

At the inlet end of the muffler housing and secured to the innersurfaces of the upper and lower sections by spot welding 9, I haveprovided the rearwardly extending converging perforated baffles I0 and Hwhich are slightly bowed transversely and extend the full Width of themuffler housing at that point. These baflles l0 and II are bent adjacenttheir rear ends to form the flattened parallel extending terminal ends12 and I3 and are slightly spaced to direct the exhaust gassesrearwardly along the interior of the muffier.

A second pair of perforated baffle plates l4 and 15 extend transverselyof the muffler sections I and 2, and are suitably secured thereto andconverge or slope toward each other from the front end of the mufflertoward the rear thereof, and terminate in the spaced parallel extendingterminal ends 16 and I1, which are in alignment with the terminal ends[2 and l3 of the baffle plates I0 and II, but to the rear thereof.

A transversely extending deflector plate I8 is spot welded at H! to theopposite sides of the upper muffler section I, and is formed with theperforations 20 adjacent its forward end and the perforations 2'!adjacent its rear end. The plate 18 slopes downwardly from its front endto its rear end and is bent upwardly as at 22 adjacent its rear end. Thepurpose of the deflector plate I8nis to prevent trapping or pocketing ofthe exhaust gasses in the front end of the muffler, particularly betweenthe baffle plate 14 and the deflector plate l8.

A forwardly sloping deflector plate 23 extends transversely of themuffler housing from a .point a short distance below the top of theupper muffler section I where it is spot welded at 24, to the bottom ofthe lower mufiier section 2, thereby acting to direct all of the exhaustgasses rearwardly and to discharge the said gasses through therestricted opening formed by the upper rear end of the deflector plate23 and the adjacent top of the top muffler section I.

A short forwardly sloping deflector plate 25 extends transversely acrossthe muffler housing for the exhaust sounds and stops the acousticsbetween the said plates 2'! and 28. The plate 21 is spot welded at 29 tothe top of the mufiler housing and extends downwardly therefrom and isbent at right angles thereto, and extends forwardly to a pointintermediate the deflector plates 23 and 25, where it is again bent toextend parallel with and between the said plates 23 and 25.

The plate 21 is also spot welded at 30 and 3| to the sides of themuffler housing, shown in Figure 4 of the drawings.

The baffle .or deflector plate 28 is spot welded at 32 to the top of themuffler housing and extends downwardly therefrom and is bent at rightangles to extend forwardly to a point between the deflector plates 23and 21. Perforations 33 are formed through the upper portion of theplate 28 so that the remaining exhaust noises will be cushioned as theypass through these perforations, and the noises will be stopped ortrapped between the plates 28 and 29. The flow of exhaust gasses willthen be directed forwardly between the deflector plates 23 and 29, andthen rearwardly between the plates 25 and 29, where the gasses will passout of the muffler to and through the tail pipe (not shown).

From the foregoing description it will be apparent that I have devised ahighly eficient form of muffler which will efiiciently silence thenoises from an internal combustion motor, and will reduce pocketing orback pressure .of the exhaust gasses to a minimum. By inspection ofFigure 4 of the drawings it will be apparent that the exhaust gassesenter the front end 7 of the muffler and pass through the perforationsin the bafile plates Ill and through the restricted opening between thetransverse parallel tail ends l2 and I3 of the baffles f and l I. Itwill be understood that some of the gasses pass through the perforationsand some of the gasses pass between the tail ends [2 and l 3. The gasseswill then be deflected rearwardly where they will pass through theperforated deflector plates or baffles 14 and I5, and also some of thegasses will pass through the restricted opening between the paralleltransverse tail ends l6 and ll of the said baffles l4 and IS.

The exhaust gasses will then be directed to and through the deflectorplate I8 and along the upper surface of the deflector plate 23 and fromthis point through the restricted opening at the rear end of saiddeflector plate 23 and the top of the muffler housing. The deflectorplate l8 with its arrangements of perforations 2a and 2| serves toprevent any pocketing or trapping of the exhaust gasses at this forwardend of the muffler and the upturned tail end 22 of the deflector platef8 will direct the exhaust gasses toward the restricted openings formedby the deflector plate 23 at the top of the muffler housing ashereinbefore described.

The flow of exhaust gasses will pass through the perforations 33 in theplate or baffle 28 and into the space between the said plate or baffle23 and the baffle 27, whereupon the gasses will be as clearly exhaustgasses to said directed forwardly and down between the forward portionof the baffle 21 and the deflector plate 23. From this point the gasseswill then be directed rearwardly between the baflles or deflector plates25 and 2'! to the rear end of the muffler where they will pass from themuffler and to and through the tail pipe (not shown). As hereinbeforedescribed and mentioned the formation ,of the deflector of baffle plates28 and 29 with the perforation 33 in the plate 28 serves to cushion andstop the exhaust sounds so that practically no noise will be emittedfrom the rear end of the muffler. It has been found that internalcombustion engines equipped with mufflers formed in accordance with myinvention, are highly efficient, and due to the fact that there issubstantially no back pressure in the muffler, I have been able to runmore miles per gallon of gasoline when using this mufller than possiblewhen using mufflers now on the market.

While I have described and illustrated my preferred form of invention,it will be understood that I do not intend to limit myself to thisspecific construction, as many minor changes in detail of constructionmay be resorted to without departure from the spirit of the invention.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. An engine muffler comprising a housing having upper and lowersections connected along their opposite sides, a tortuous path of travelfor exhaust gases defined in said housing and including nested pairs ofrearwardly converging perforated baffle plates positioned adjacent thefront ends of said muffler and terminating in restricted longitudinallyaligned end inlet passages, a pair of cooperating angular deflectorbaffle plates positioned adjacent the rear of said muffler, one of saidlast mentioned plates being perforated, a rearwardly sloping perforateddeflector plate positioned adjacent said front baffle plates and havingan upwardly angularly extended terminal end disposed adjacent the inletpassageways for directing the I rear baffle plates, an elongatedupwardly sloping imperforate deflector plate extending rearwardly fromthe bottom of the mufller housing to a point adjacent the rear ballieplates, said deflector plate being spaced from the top of the mufflerhousing thereby forming a restricted opening through which exhaustgasses will be directed toward the rear baffle plate, said angularterminal and elongated plate defining a selected rearwardly extendingpassageway and an upwardly sloping short deflector plate extendingbetween the sides of the muffler hous-' ing from the bottom of themuffler housing to a point below the rear baffle plate, said shortdeflector plate being parallel to said elongated deflector plate andlying below the same forming a restricted outlet passage.

2. An engine muffler comprising a housing having upper and lowersections connected along their opposite sides, a tortuous path of travelfor exhaust gases defined in said housing and including a plurality ofnested rearwardly converging perforated baffle plates positionedadjacent the front end of said housing and terminating in restrictedlongitudinally aligned inlet passageways, a pair of cooperating angulardeflector baffle plates positioned adjacent the rear end of said housingat the top thereof, one of said last named baffle plates beingperforated, a rearwardly sloping deflector plate positioned intermediatesaid front and rear baffle plates and having an,

upwardly extending terminal end spaced from said housing and disposedadjacent the inlet passageways to direct the exhaust gases toward saidrear baffle plates, an elongated upwardly sloping deflector plateextending rearwardly from the bottom of the housing to a point adjacentthe rear bailie plates and spaced from the top of the housing to definea restricted passageway at the top of the housing to the rear baffleplates and an upwardly sloping short deflector plate positioned parallelto and below the elongated deflector plate.

3. An engine muffler comprising a housing having opposed ends providedwith longitudinally aligned openings defining an inlet and an outlet,nested pairs of rearwardly converging perforated baffle platespositioned adjacent the inlet end of the housing and terminating inrestricted longitudinally aligned inlet passageways, a pair ofcooperating angular inner and outer deflector bafiie plates positionedadjacent the outlet end of the housing, said inner plate beingperforated, a rearwardly and downwardly sloping perforated deflectorplate positioned in front of said nested inlet baiile plates and havingan upwardly extended terminal end disposed adjacent the inletpassageways in the plates, said terminal end being adapted to direct theexhaust gases to said outlet baiiie plates, an elongated upwardlysloping deflector plate positioned below the nested inlet bafiie platesand extending rearwardly from the bottom of the housing to a pointspaced from the top adjacent the outlet baiiie 6 plates to define arestricted opening through which the exhaust gases will be directedtowards the outlet bafile plates, said terminal end and elongated baffleplate being disposed in substantial parallelism and defining arestricted passageway, an upwardly sloping short deflector plateextending between the sides of the housing from the bottom thereof to apoint below the outlet baiile plates, said short deflector plate beingparallel to said elongated plate and positioned below the same, and saidouter outlet baffle plate being provided with an angular downwardlyextending end directed between the short deflector plate and elongateddeflector plate.

PATRICK J. MAY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 980,064 Carrick Dec. 27, 19101,169,030 Hardy Jan. 18, 1916 1,182,611 Williams and Weaver May 9, 19161,452,435 Pullin Apr. 17, 1928 1,474,115 Heather Nov. 13, 1923 1,685,701Blanchard Sept. 25, 1928 1,688,488 Dormeyer Oct. 23, 1928 2,010,175Boysen Aug. 6, 1935 2,122,086 Chase June 28, 1938

